Multiple-use biopsy apparatus and corresponding single-use biopsy instrument

ABSTRACT

A single-use biopsy instrument for mounting at a multiple-use biopsy apparatus, comprises a cartridge enclosing proximal end portions of a canula, a finger tube slidingly disposed on the canula, and a stylet slidingly disposed in the canula. The canula and the finger tube have proximal holding portions and are displaceable in regard of the cartridge by displacement means disposed in the biopsy apparatus engaging with the holding portions through one or several engagement openings in one wall of the cartridge. Also disclosed is a corresponding biopsy apparatus.

FIELD OF THE INVENTION

[0001] The present invention relates to a multiple-use biopsy apparatus.The present invention also relates to a single-use biopsy instrument foruse with the biopsy apparatus of the invention.

BACKGROUND OF THE INVENTION

[0002] The invention departs from an apparatus for collecting tissuesamples by excising a segment from tissue, and a corresponding methodfor harvesting of tissue samples described in WO 99/44505 which isincorporated by reference into this specification. The biopsy apparatusof WO 99/44505 comprises a biopsy instrument and a holder.

[0003] In this specification, the terms “proximal” and “distal” refer tothe person extracting a biopsy sample; the terms “front” and “rear” havea corresponding meaning. Thus, the proximal end of a biopsy apparatus isits rear end, pointing away from the patient.

[0004] The biopsy instrument of WO 99/44505 comprises a canula with adistal open cutting end and a through opening in its wall near thedistal end, a finger tube slidingly disposed on the canula and providedwith a finger at its distal end, and a stylet slidingly disposed in thecanula, the finger being insertable into the opening in the canula walland axially displaceable in a forward direction so as to be deflectedtowards the axis of the canula.

[0005] The holder of WO 99/44505 comprises a housing, means forreleasably coupling the biopsy instrument to the housing; and compressedcoil means for consecutive axial displacement of the canula and the tubein combination in a distal direction, and of the tube in respect of thecanula in the same direction. To expulse a harvested biopsy sample fromthe canula, the further comprises means for consecutive displacement ofthe tube, and of the tube and the canula in combination, in a proximaldirection. At their respective distal ends the canula, the tube and thestylet are provided with end sections for mounting in the holder.

[0006] WO 99/44504 also discloses a loading assembly for the holder. Theloading assembly comprises a loading arm swivellingly attached at itsone end to the housing, a intermediate arm swivellingly attached at itsone end to the loading arm and at its other end to a catch holding thecanula end section during tensioning and in a tensioned position inrespect of a tension spring or during compression or in a compressedposition in respect of a compression spring (the latter beingpreferred), the catch being displaceable in a proximal direction againstthe resistance of the spring and being adapted to be held there forintentional release.

[0007] A biopsy apparatus comprising the holder and the loading assemblyof WO 99/44504 can be manufactured for single use in which case it issupplied to the customer preferably with the biopsy instrument of WO99/44505 already mounted. It can, however, also be designed for repeateduse with disposable sets of the biopsy instrument.

[0008] The aforementioned biopsy apparatus intended for single use, thatis, provided to the user with the biopsy instrument already mounted,does not require other manual skills than performing its proper medicaloperation, that is, taking a biopsy sample from a patient and expellingthe sample from the canula thereafter.

[0009] This is not so with the multiple-use biopsy apparatus in which anew biopsy instrument has to be mounted for each biopsy. Since thebiopsy apparatus comprises three parts which are slidingly displaceablein regard of each other, their mounting, in a given spatialrelationship, requires skilful handling. To this adds the sharp tip ofthe stylet and the front edge of the canula which may cause wounds ifnot properly handled in mounting or may be accidentally damaged, as maybe the tiny tissue excision means, that is the finger of the fingertube. Thus there is ample room for improvement in respect of making theloading process a routine measure, including modification of the biopsyapparatus and the loading assembly.

OBJECTS OF THE INVENTION

[0010] It is an object of the invention to provide a biopsy apparatuscomprising a loading assembly for multiple use in which a disposablebiopsy instrument can be easily and safely mounted and dismounted.

[0011] It is an object of the invention to provide a correspondingbiopsy instrument.

[0012] Additional objects of the invention will become obvious from thefollowing short description of the invention, the accompanying drawingsillustrating a preferred embodiment of the invention described ingreater detail, and the appended claims.

SUMMARY OF THE INVENTION

[0013] These and other objects of the invention are achieved by asingle-use biopsy instrument of the aforementioned kind designed formounting in a multiple-use biopsy apparatus, the biopsy instrumentincluding a cartridge enclosing proximal end portions of the canula, thefinger tube, and the stylet, the cartridge being provided with adisplaceable lock on one of its sides, the displacement beingsubstantially in the lock plane and in a proximal direction. It ispreferred for the cartridge to comprise a safety latch which must beremoved before the lock can be displaced. By removing the safety latchand displacing the lock in a proximal direction the biopsy instrument isprepared for mounting at the biopsy apparatus of the invention.

[0014] In particular the single-use biopsy instrument for mounting at amultiple-use biopsy apparatus includes a cartridge enclosing proximalend portions of a canula, a finger tube slidingly disposed on thecanula, and a stylet slidingly disposed in the canula, the canula andthe finger tube having proximal holding portions and being displaceablein regard of the cartridge by displacement means disposed in the biopsyapparatus engaging with said holding portions through one or severalengagement openings in one wall of the cartridge.

[0015] It is preferred for the cartridge to comprise a cartridge bodyhaving an opening on one of its sides covered by a lock in which saidone or several engagement openings are disposed. The displacementopening is advantageously a slit extending in parallel with the canula.

[0016] According to a first preferred aspect of the invention, thecartridge lock extends outside the cartridge body opening and isdisplaceable in the lock plane in the direction of the cartridge body soas to cover the opening of the cartridge body opening more fully. It isadvantageous for the cartridge lock to be securable in a displacedposition at the cartridge body or at an element secured thereat.

[0017] According to a second preferred aspect of the invention, thebiopsy instrument comprises a removable safety latch partly covering thecartridge body opening. It is particularly preferred for the cartridgelock to be displaceable only upon removal of a safety latch covering aportion of the cartridge body opening.

[0018] According to a third preferred aspect of the invention, theholding portion of the stylet is fixed to the cartridge body.

[0019] According to a fourth preferred aspect of the invention, thecartridge body comprises laterally disposed projections for mounting inhooks of the biopsy apparatus.

[0020] According to the present invention is also disclosed a biopsyapparatus comprising a casing, means for releasably coupling the biopsyinstrument of the invention to the casing, compressed coil meansdisposed in the casing for consecutive axial displacement of the canulaand the finger tube in combination in a distal direction, and of thetube in respect of the canula in the same direction, the displacementbeing effected via a first displacement member slidingly disposed in thecasing cooperating with a proximal end portion of the canula of and asecond displacement member slidingly disposed in the casing distally ofthe first displacement member cooperating with a proximal end portion ofthe finger tube.

[0021] According to a fifth preferred aspect of the invention, the firstand second displacement members comprise pins extending through alongitudinal slit in the cartridge lock which are engageable withcorresponding bores in the end portions of the canula and the fingertube.

[0022] According to a sixth preferred aspect of the invention, thebiopsy apparatus comprises a mechanism for step-less control of thecanula stroke.

[0023] According to a seventh preferred aspect of the invention, thebiopsy apparatus is designed to receive the entire biopsy instrumentcartridge in an opening disposed on one of its sides so as to make thevisible side of the cartridge (the cartridge bottom) flush with portionsof the same side of the biopsy instrument. It is important for thebiopsy instrument cartridge to be relaseably securable in said opening.Preferably the biopsy instrument is securable by means of an axiallydisplaceable frame comprising hooks disposed in the opening, the hooksbeing releaseably engageable with laterally disposed projections of thecartridge body.

[0024] According to an eight preferred aspect of the invention, thebiopsy apparatus is provided with a loading mechanism for compression ofa spring coil affecting said first and second displacement members, themechanism comprising a loading arm, a loading catch and an intermediatearm swivellingly fixed at the loading arm and the loading catch. It ispreferred for the apparatus to comprise means for releasing the firstand second displacement members in combination to displace them in adistal direction by the action of the spring coil. Also preferred is forthe apparatus to comprise a stroke limiter for limiting the displacementof the second and/or the first displacement member in a distaldirection. Preferably the displacement of the second displacement memberis so limited as to make it displaceable further in a distal directionthan the first displacement member.

[0025] According to still another preferred aspect of the invention, thebiopsy apparatus comprises means for expulsion of a harvested biopsysample from the canula.

[0026] By definition, the top side of the biopsy instrument of theinvention is the side covered by a lock. The top side of the biopsyapparatus of the invention is the side provided with the loadingmechanism. The biopsy instrument is mounted at the bottom side of biopsyapparatus with its top side facing the apparatus.

[0027] The invention will now be described by reference to preferredembodiments of the biopsy instrument of the invention and the biopsyapparatus of the invention, by the study of which further advantages ofthe present invention will become obvious. The preferred embodiments areillustrated in drawings showing rough perspective views thereof.

DESCRIPTION OF THE DRAWINGS

[0028] The drawings illustrate the following:

[0029]FIG. 1 a preferred embodiment of the biopsy apparatus of theinvention, with a biopsy instrument mounted, in a proximal side/bottomview, with the loading arm abutting the casing;

[0030]FIG. 2 the biopsy apparatus of FIG. 1 in a distal side/top view,with the loading arm raised;

[0031]FIG. 3 the biopsy apparatus of FIG. 1, in a distal side/bottomview, with the biopsy instrument removed;

[0032]FIG. 4 the biopsy apparatus of FIG. 2 and in the same view, withthe casing and part of the loading mechanism removed, in a securedloaded condition;

[0033]FIG. 5 the biopsy apparatus of FIG. 4 and in the same view andcondition, with a shorter stroke length set;

[0034]FIG. 6 the biopsy apparatus of FIG. 5, in the same view, in anunsecured loaded condition;

[0035]FIG. 7 the biopsy apparatus of FIG. 5, in the same view, in areleased condition at the end of the canula movement;

[0036]FIG. 8 the biopsy apparatus of FIG. 5, in the same view, in areleased condition at the end of the finger tube movement;

[0037]FIG. 9 the biopsy apparatus of FIG. 5, in the same view, afterwithdrawal of the finger from the canula but before sample expulsion andloading;

[0038]FIG. 10 the biopsy apparatus of FIG. 5, in a frontal top view,after sample expulsion;

[0039]FIG. 11 the biopsy apparatus of FIG. 5 but with the loading armshown, in the same view, at the start of a loading operation;

[0040]FIG. 12 the biopsy apparatus of FIGS. 11, at the end of a loadingoperation;

[0041]FIG. 13 the biopsy instrument of FIG. 1, in a top/proximal view,complete with the safety latch;

[0042]FIG. 14 the biopsy instrument of FIG. 1, in another top/proximalview, with the safety latch removed and the cartridge lock inserted;

[0043]FIG. 15 the biopsy instrument of FIG. 1, in still anothertop/proximal view, with the cartridge lock removed;

[0044]FIG. 16 the biopsy instrument of FIG. 1, in an explodedtop/proximal view, without the safety latch;

[0045]FIG. 17 the cartridge lock and safety latch of the biopsyinstrument in FIG. 1, in a bottom/proximal perspective view, aligned butslightly separated;

[0046]FIG. 18 the cartridge body of the biopsy instrument in FIG. 1, ina front/proximal view;

[0047]FIG. 19 the cartridge mounting frame, in a top/proximal view.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0048] Indications of lateral direction such as ‘from above’,‘underside’, ‘top side’ are defined by the views of the Figures. Thesteel coil compression springs are only shown schematically ascylinders.

[0049] The biopsy instrument illustrated in FIGS. 1 and 13-19 comprisesa canula, a finger tube 201 and a stylet 301 of the same kind asillustrated in FIG. 4 of WO 99/44505; see also U.S. Pat. No. 5,644,542,where the design and function of these elements is explained in detailand which is incorporated herein by reference. In FIG. 29 rear(proximal) end portions of the finger tube 201 enclosing the canula andthe stylet 301 are shown to illustrate their relationship with theirrespective holders 200, 300, each made in one piece of a polymermaterial, preferably an ABS polymer (acrylonitrile-butadiene-styrenecopolymer) or another polymer of high impact and tensile strength. Alsoshown in FIG. 29 is the canula holder 100.

[0050] The canula, the finger tube 201 and the stylet 301 are mounted ina cartridge body 700, a distal portion of which is covered a lock 701and an portion adjoining thereto proximally by a safety latch 702. Thecartridge lock 701 extends over the distal end of the cartridge body 700and is held by projectures 706,707 in lateral slits 704, 705 of thelatter so that it can be displaced in a distal direction upon removal ofthe safety latch 702 to cover most of the cartridge body 700. Initially,the safety latch 702 is positionally stabilized in respect of thecartridge lock by pegs 708 extending from its distal end wall insertedin corresponding bores in the proximal end wall of the cartridge lock701 and a transversal flange 709 at its bottom side abutting the rearwall 710 of the cartridge body 700. It is in this configuration thebiopsy instrument of the invention is supplied to the user for mountingat the biopsy apparatus of the invention by a procedure explainedfurther down. The canula, the stylet 301 and the finger tube 201 aremounted in the cartridge body 700 in an assembled state, that is withthe canula inserted in the finger tube 301 and the stylet 201 in thecanula. The canula, the stylet and the finger tube extend through a slit703 in the front wall of the cartridge body 700 in a distal direction.The neck 302 of the stylet holder 300 which has an I-profile is snappedbetween two snap tonges 713 extending from the bottom 714 of thecartridge body 700. The stylet 301 thus is rigidly secured at thecartridge body 700. In contrast, the canula and finger tube 201 are notdefinitely fixed but only constrained in their movement inside thecartridge. The distal wall of a lateral notch 715 inside of thecartridge lock 701 cooperates with the tip 214 of a tongue 213 of thefinger tube holder 200 projecting above its top face. Thereby the fingertube holder 200 and canula holder 100 proximally abutting thereto can bedisplaced in a proximal direction by pushing the cartridge lock 701fully over the cartridge body 700, once the safety latch 702 has beenremoved by pulling it rearwards while lifting it slightly so as todisengage its transversal flange 709 from the rear wall 710 of thecartridge body. The cartridge lock 701 is pushed back until a snaptongue 716 extending from its proximal end wall engages with an elevatedtransverse portion 304 of the stylet holder 300. This makes the biopsyinstrument ready for mounting at the biopsy apparatus.

[0051] The biopsy apparatus of the invention comprises a casing 500consisting of two substantially symmetrical halves sectionedperpendicular to the larger faces of the holders 100, 200. The casing500 which has about the form of a rectangular bar can be of a suitablepolymer, for instance polycarbonate, but preferably of metal, such asaluminum or stainless steel, since the biopsy apparatus has to withstandrough cleaning and sterilizing conditions. The casing halves fit byappropriate design of rims and other elements, such as snaps (not shown)but may also be connected by bolts or similar means. The casing includesa loading assembly according to WO 99/44505 to which reference is madeand by which holders 100, 200 are brought to a ‘loaded’ position fromwhich they can be released for tissue sampling. Instead of the singlespring coil of the apparatus of WO 99/44505 three spring coils 601disposed in parallel are provided; for simplicity reasons they are onlyshown as cylinders in the drawings.

[0052] In contrast to the arrangement in WO 99/44505 in which theholders 100, 200 of the biopsy instrument are directly displaced againstthe force of a spring coil in the loading procedure, the presentinvention employs intermediate structures pertaining to the biopsyapparatus termed finger tube and canula control members 543,544 whichprovide for control of the biopsy instrument by the biopsy apparatus.The finger tube and canula control members have coupling pins disposedat their lower faces for engagement with the finger tube holder and thecanula holder, respectively,. The finger tube control member 543 has onepair of coupling pins 546, the canula control member 544 also has onepair 547. In addition the finger tube control member has a pair of guidepins 548 disposed distally of the finger tube coupling pins 546 whichguide pins 548 are shorter than the coupling pins. Thus twolongitudinally extending parallel rows of coupling and guide pinsresult. The coupling pins of each pin row are arranged to engage withcorresponding bores disposed in the finger tube holder bores 210, andthe canula holder, bores 110. The control members 543,544 with theirguide and coupling pins are accessible from outside through an openingin the bottom wall of the casing 500. The opening is of a size allowingthe cartridge to be fully inserted and secured in the inserted positionby an axially displaceable mounting frame 570 comprising pairs of hooks571,572 which engage with rectangular front and rear shoulders 720,721extending laterally from the cartridge body 700. The mounting frame 570can be operated from outside by knobs 573 extending through openings inthe lateral walls of the casing 500. The engagement of the pairs ofcoupling pins 546, 547 of the control members 543,544 with the pairs ofbores 210,110 in the finger tube holder 200 and the canula holder 100,respectively, is provided for by two longitudinally extending slits730,731 in the cartridge lock 701. To provide for easy loading theloading assembly employs three elements, a loading arm 520, aintermediate arm 530, and a loading catch 540 comprising a catch arm 541holding the finger tube control member 543 during compression of thespring coils 601 and in their compressed (loaded) state. With itshook-like front end of the catch arm 541 the catch 540 grips a loadinggrip 542 of the finger tube control member 543. The canula controlmember 544 is in turn held in position by the finger tube control member543. The canula holder/finger tube holder assembly 100, 200 can bereleased from the loaded state by an oblong trigger 600 disposeddistally/laterally of the catch 540. The rear end of trigger 600 forminga release button 602 passes through an opening in the rear wall of thecasing 500. By pressing the release button 602 the trigger 600 is pushedforwards whereby a slanting portion 603 of it affects a slanting rearface 549 of the catch arm 541 which is journalled at 545, so to make itswivel by a few degrees, thereby releasing the grip 542 and, hence, thefinger tube control member 543 and the finger tube holder 200. Thebiopsy apparatus can be secured in the loaded position by a transverselydisplaceable locker pin 604 disposed near the rear end of the housing inthrough bores 605 of the casing. In a secured position the locker pin604 cooperates with an arc-formed cutout of the trigger 600.

[0053] A biopsy sampling cycle will now be explained by reference toFIGS. 4-10. In FIG. 4 the biopsy instrument is in a loaded and securedposition. In FIG. 5 the stroke length has been reduced from themaximally possible by displacing the stroke limiter 580 in a distaldirection by means of a screw mechanism of which the screw 581 and theknob 582 disposed at the front face of the biopsy apparatus forcontinuous setting the stroke length is shown, whereas an additionalrelease mechanism by which any stroke setting can be released to providefor maximum stroke length setting is not shown. Next (FIG. 6), thelocker pin 604 is unsecured (the stylet 301 will have been injected intothe tissue at this stage but this is not shown) and the trigger 600 ispushed forwards by pressing the release button 602; The figure shows thesituation just after the front end of the catch arm has released theloading grip 542 of the finger tube control member 543. In FIG. 7 thesituation at the end of the first phase of biopsy sampling is shown,that is when the combined distal movement of the canula and the fingertube 201 along the stylet 301 has come to an end whereby the distalmovement of the canula is stopped by the front face of the canulacontrol member 544 hitting the side bar end faces of the U-formed strokelimiter 580. FIG. 8 illustrates the situation at the end of the secondphase of biopsy sampling, that is when the distal movement of the fingertube 201 is stopped by the base of the U-formed stroke limiter 580. InFIG. 9 the person taking a biopsy sample has ceased the thumb pressureon the release button 602. This allows the catch arm 541 to swivel backto its original position, thereby permitting a spring-loaded (at 550)L-formed lever 554 to swing by a few degrees around a pinion 551 bywhich it is fixed at upper face of the finger tube control member 543.At its frontal transversal section the L-formed lever 554 has anL-shaped through opening 555 with the same orientation as the lever 554.A pin 556 extending from the upper face of the canula control member 544extends into the opening 555 in which it had been disposed up to nowalong the vertical L-bar of the opening 555. By the slight rotation ofthe lever the pin 556 is now located at the free end of the transversalL-bar of the opening 555 while the finger tube control member 543 hasbeen slightly withdrawn from the canula control member which issufficient for withdrawing the finger tip of the finger tube 201 fromthe opening in the canula wall. This, in combination with the release(not shown) of the stroke limiter 580 to allow it to moved back to the,maximum stroke position, provides for the ejection of the biopsy samplefrom the canula in the next step, the situation at the end of which isillustrated in FIG. 10. Thereafter the biopsy apparatus is again loadedand the used biopsy instrument released from the apparatus by displacingthe mounting frame 570 in a distal direction by means of knobs 571.

1. A single-use biopsy instrument for mounting at a multiple-use biopsyapparatus, the biopsy instrument comprising a cartridge enclosingproximal end portions of a canula, a finger tube slidingly disposed onthe canula, and a stylet slidingly disposed in the canula, the canulaand the finger tube having proximal holding portions and beingdisplaceable in regard of the cartridge by displacement means disposedin the biopsy apparatus engaging with said holding portions through oneor several engagement openings in one wall of the cartridge.
 2. Thebiopsy instrument of claim 1, wherein the cartridge comprises acartridge body having an opening on one of its sides covered by a lockin which said one or several engagement openings are disposed.
 3. Thebiopsy instrument of claim 2, wherein said displacement opening is aslit extending in parallel with the canula.
 4. The biopsy instrument ofclaim 2, wherein the cartridge lock extends outside the cartridge bodyopening and is displaceable in the lock plane in the direction of thecartridge body so as to cover the opening of the cartridge body openingmore fully.
 5. The biopsy instrument of claim 4, wherein the cartridgelock is securable at the cartridge body or an element secured in adisplaced position.
 6. The biopsy instrument of claim 2, comprising aremovable safety latch partly covering the cartridge body opening. 7.The biopsy instrument of claim 4, wherein the cartridge lock isdisplaceable only upon removal of a safety latch covering a portion ofthe cartridge body opening.
 8. The biopsy instrument of claim 1, whereinthe holding portion of the stylet is fixed to the cartridge body.
 9. Thebiopsy instrument of claim 1, wherein the cartridge body compriseslaterally disposed projections for mounting in hooks of the biopsyapparatus.
 10. A biopsy apparatus comprising a casing, means forreleasably coupling the biopsy instrument of claims 1-9 to the casing,compressed coil means disposed in the casing for consecutive axialdisplacement of the canula and the finger tube in combination in adistal direction, and of the tube in respect of the canula in the samedirection, the displacement being effected via a first displacementmember slidingly disposed in the casing cooperating with a proximal endportion of the canula of and a second displacement member slidinglydisposed in the casing distally of the first displacement membercooperating with a proximal end portion of the finger tube.
 11. Thebiopsy apparatus of claim 10, wherein said first and second displacementmembers comprise pins extending through a longitudinal slit in thecartridge lock engageable with corresponding bores in the end portionsof the canula and the finger tube.
 12. The biopsy apparatus of claim 10,comprising a mechanism for step-less control of the canula stroke. 13.The biopsy apparatus of claim 10, designed to receive the entire biopsyinstrument cartridge in an opening disposed on one of its sides.
 14. Thebiopsy apparatus of claim 13, wherein the biopsy instrument cartridge isrelaseably securable in said opening.
 15. The biopsy apparatus of claim14, wherein the biopsy instrument is securable by means of an axiallydisplaceable frame comprising hooks disposed in the opening, the hooksbeing releaseably engageable with laterally disposed projections of thecartridge body.
 16. The biopsy apparatus of claim 10, provided with aloading mechanism for compression of a spring coil affecting said firstand second displacement members, the mechanism comprising a loading arm,a loading catch and an intermediate arm swivellingly fixed at theloading arm and the loading catch.
 17. The biopsy apparatus of claim 11,comprising means for releasing the first and second displacement membersin combination to displace them in a distal direction by the action ofthe spring coil.
 18. The biopsy apparatus of claim 17, comprising astroke limiter for limiting the displacement of the second displacementmember in a distal direction.
 19. The biopsy apparatus of claim 17,comprising a stroke limiter for limiting the displacement of the firstdisplacement member in a distal direction.
 20. The biopsy apparatus ofclaim 19, wherein the displacement of the second displacement member isso limited as to make it displaceable further in a distal direction thanthe first displacement member.
 21. The biopsy apparatus of claim 10,comprising means for expulsion of a harvested biopsy sample from thecanula.